Brush construction



April 12, 1960 K. E. WEILER BRUSH CONSTRUCTION Filed Au 21, 1958 FlG3 FKB 2 FIG INVENTOR. KARL E. WEILER BRUSH CONSTRUCTION Karl E. Weiler, Buck Hill Falls, Pa., assignor to Weller Brush Company Inc., Cresco, Pa.

Application August 21, 1958, Serial No. 756,421

1 Claim. (Cl. 15 -180) This invention relates to small single tuft power driven brushes and more particularly to such brushes having non-scratching heads.

Brushes made'according to the invention are primarily used by mold makers for polishing the interior cavities of molds. Prior brushes of this type were made with a metal hand holding the tuft onto a shaft. The brush is operated by inserting the shaft into a portable power driven tool, and it rotates at very high speed. The major difficulty with the metal head brushes is that it is practically impossible to avoid contact of the head with portions of the moldvwhich resulted in scratching of the mold surface. Sincescratching of the mold can not be tolerated, the present brush was developed which eliminates the metal head and substitutes a plastic head, preferably of nylon.

The major problem was to affix the tuft of material to the nylon head in a permanent manner. Since the head is of thin wall construction, there is not sufiicient body to merely force the tuft into the head to be held by friction. The necessary force required for this would cause splitting of the thin wall. The present invention solves the problem by injection molding the hollow nylon head onto a roughened or knurled portion of the shaft, then inserting the brush material and stapling it into the head. g

Accordingly, a principal object; of the invention is to provide new and improved power driven brushmeans.

Another object of the invention is to provide new and" improved power driven brush means having a nonscratching plastic head.

Another object of the invention is to provide new and improved single tuft brush means having a thin wall plastic head.

Another-object of the invention is to provide new and improved methods of brush construction having a thin wall plastic head.

Another object of the invention is to provide new and improved brush means comprising a thin wall hollow plastic head molded onto a shaft and adapted to be power driven, and a tuft of brush material stapled into said head.

These and other objects of the .inventionjwill be apparent from the following specifications and drawings, of which: v i

Figure 1 is a sectional view withoutthe tuft.

Figure 2 is a sectional view displaced 90 from Figure 1 including the tuft, and

Figure 3 is a side view of the completed brush.

Referring to the figures, the brush according to the present invention is constructed by aflixing' a hollow thin Y United States Patent required to hold the shaft or the tuft 1 roughened portion.

2,932,050 Patented Apr. 12, 1960 wall head member'l to a shaft 2, the other end of which is adapted to be mounted in a power tool. The preferable method of aflixing the head to the shaft is by first roughening or knurling the end portion 3 of the side of the shaft and injection molding the head 1 onto the In order to keep the brush small for its intended use for polishing small interior cavities in metal, the head necessarily has a thin wall construction. This thin wall construction will not permit force fitting of'the shaft or the tuft of brush material since the force by friction would split the thin wall of the head.

The tuft is inserted by stapling it into the head which is preferably of nylon. This is done by folding the tuft T and wrapping the wire staple 4 around the center fold of thetuft and pressing the ends 5 and 6 of the wire staple into the relatively soft interior sides of the nylon head. To prevent splitting of the thin wall plastic head when inserting wire clad tuft, same is held between steel jaws which are in closed position at time The jaw jig inserts the tuft and drives the jaws are then opened and removed.

It has been found after considerable research that this is the preferable method of affixing a tuft of brush material to a thin wall flexible head. The tuft material is preferably of horse hair or hog bristle. However, plastic filament, wire or other fibers may be used. The present brush may be made in a range of diameters starting from as small as A The shaft diameters range from :y32I! The present construction is not limited to polishing,

of metal molds, but may be used wherever a small, safe, non-scratching power driven brush is used. For instance, the brush may be used in polishing fine work such as jewelry, ornamental stones, intricate metal scroll work, intricate designs on silver, or for dental work.

A power driven-brush for inaccessible places having a non-scratching head comprising a shaft having a knurled side portion on one end, a hollow thin wall plastic head molded onto saidknurled portion, a tuft of brush material folded in half and inserted in said head, a staple inserted around the center fold of said tuft and laterally into said plastic head, said head being generally cylin drical and said wall having straight outside surfaces, said wall, being substantially thinner than said tuft for minimum diameter fora given size tuft, more than half of said tuft being mounted in said head whereby said wall forms said tuft in substantially cylindrical form for even pressure high speed rotational polishing.

" References Cited in the file of this patent UNITED STATES PATENTS 47,157 White Apr. 4, 1865 301,936 Swase'y July 15,1884, 372,385 Read Nov. 1, 1887 800,291 Graul Sept. 26, 1905 2,160,836 Davids June 6, 1939 2,255,184 Osenberg Sept. 9, 1941 2,643,157 Hardman et al. June 23, 1953 FOREIGN PATENTS 359.712 Italy June 3, 1938 

